Integrated system for processing semiconductor wafers

ABSTRACT

An integrated process tool for chemical mechanical processing, cleaning and drying a semiconductor workpiece is provided. The integrated process tool includes a CMP module and a cleaning and drying module. After being processed, the workpiece is transported from the CMP module to the cleaning and drying module using a movable housing. In the cleaning and drying module, a cleaning mechanism is used to clean the workpiece while the workpiece is rotated and held by a support stucture of the movable housing. A drying mechanism of the cleaning and drying module picks up the workpiece from the moveable housing and spin dries it. Throughout the CMP process, cleaning and drying, the processed surface of the wafer faces down.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.10/369,118, filed Feb. 18, 2003, which is a continuation in part of U.S.application Ser. No. 09/795,687, filed Feb. 27, 2001, now U.S. Pat. No.6,953,392, which claims priority from U.S. provisional application Nos.60/259,676, filed Jan. 5, 2001, and 60/261,263, filed Jan. 16, 2001, allof which are entirely incorporated herein by reference. This applicationalso claims priority by way of U.S. application Ser. No. 10/369,118 toU.S. provisional application Nos. 60/357,148, filed Feb. 15, 2002, and60/397,740, filed Jul. 20, 2002, all of which are entirely incorporatedherein by reference.

FIELD OF THE INVENTION

The present invention relates to semiconductor processing technologiesand, more particularly, to an integrated system for processingsemiconductor wafers. The invention also includes individual processmodules for performing specific tasks, for example, a workpiece cleaningand drying module.

BACKGROUND OF THE INVENTION

In the semiconductor industry, various processes can be used to depositand etch materials on wafers. Deposition techniques include processessuch as electrochemical deposition (ECD) and electro chemical mechanicaldeposition (ECMD). In both processes, a conductor is deposited on asemiconductor wafer or workpiece by having electrical current carriedthrough an electrolyte that comes into contact with the surface of theworkpiece (cathode). The ECMD process is able to uniformly fill theholes and trenches on the surface of the workpiece with the conductivematerial while maintaining the planarity of the surface. A more detaileddescription of the ECMD method and apparatus can be found in the U.S.Pat. No. 6,176,992, entitled “Method and Apparatus For Electro ChemicalMechanical Deposition”, commonly owned by the assignee of the presentinvention.

If a conventional plating process is performed to deposit the conductivematerial in a deposition chamber, the workpiece may be transferred toanother chamber in the cluster tool for chemical mechanical polishing(CMP). As is known, the material removal can also be carried out usingelectrochemical etching by making the workpiece anodic (positive) withrespect to an electrode after completing an ECD or ECMD process.

Regardless of which process is used, the workpiece is next transferredto a rinsing/cleaning station or module after the deposition and/orpolishing steps. During the rinsing/cleaning step, various residuesgenerated by the deposition and/or polishing processes are rinsed offthe workpiece with a fluid such as de-ionized water or de-ionized waterwith small amounts of other cleaning and/or passivating agents, andsubsequently the workpiece is dried.

Conventionally, processing chambers are designed in multiple processingstations or modules that are arranged in a cluster to form a clustertool or system. Such cluster tools or systems are often used to processa multiple number of workpieces at the same time. Generally, clustertools are configured with multiple processing stations or modules andare designed for a specific operation. However, in such conventionalcluster tools, deposition and cleaning processing steps both typicallyrequire separate chambers. For this reason, in known cluster tools, fora workpiece to be processed and cleaned, it must be moved to anotherstation or system. Thus, such configured systems require pickingworkpieces from a particular processing environment and placing theminto a cleaning environment. The workpiece can be cleaned and dried in acleaning and a drying module using, for example, a rinse and spinprocess, as known in the art.

When the workpiece is transferred to the cleaning and drying module,contaminants may have attached themselves on the workpiece surface. Thesource of these contaminants may be the plating/polishing agent,transferring mechanism, surrounding air, the processing facility,personnel, process chemicals, and the like. The workpiece surface shouldbe free of such contaminants; otherwise, the contaminants may affectdevice performance characteristics and may cause device failure to occurat faster rates than usual.

The speed of which the workpiece is transferred from one module to thenext is also critical. As is well known in the semiconductor industry,the production line for manufacturing the workpiece from beginning toend must be performed in the most efficient manner.

SUMMARY OF THE INVENTION

The present invention is directed to a novel cleaning and drying moduleof the overall cluster tool. The present invention further provides amore cost effective, efficient, contaminant free method and apparatusfor cleaning and dying workpieces than those currently available.

In one aspect of the present invention, an apparatus for processing,cleaning and drying a semiconductor workpiece is provided. The apparatusincludes a process area to process a surface of the workpiece and acleaning drying area to clean and dry the workpiece. A movable housingtransports the workpiece from the process area to a cleaning and dryingarea. The movable housing includes a support structure adapted to holdthe workpiece. A cleaning mechanism cleans the workpiece while theworkpiece is rotated and held by the support structure. A dryingmechanism receives the workpiece from the moveable housing for dryingthe workpiece. The workpiece is held and cleaned and dried while theprocessed surface of the workpiece faces down.

In another aspect of the present invention, a method for cleaning anddrying a workpiece in a process module, that has a cleaning and dryingsection and a process section, is provided. The method includes placingthe workpiece on a movable housing, moving the movable housing into thecleaning and drying section of the process module, cleaning a surface ofthe workpiece using a cleaning fluid in the cleaning and drying section,transferring the workpiece from the moveable housing to a dryingmechanism having a spinning wheel and drying the workpiece. Before thestep of placing the workpiece onto the movable housing, the surface ofthe workpiece is processed in the process section adjacent the cleaningand drying section of the process module prior to the step of placing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a system of the present inventionincluding an embodiment of an integrated chemical mechanical processstation of the present invention;

FIG. 2 is a schematic illustration of another system of the presentinvention including the chemical mechanical polishing process station ofthe present invention;

FIG. 3 is a schematic illustration of another system of the presentinvention including the chemical mechanical polishing process stationand an anneal station of the present invention;

FIG. 4 is a schematic illustration of the chemical mechanical polishingprocessing station of the present invention;

FIG. 5 is a schematic illustration of a cleaning drying module of thepresent invention including the cleaning and drying mechanisms accordingto one embodiment of the present invention;

FIG. 6 is a schematic illustration of a wafer indicating the relativepositions of the holding spools and the dryer clamps;

FIG. 7 is a schematic illustration of an embodiment of a wafer releaseand hold mechanism of the dryer.

FIG. 8 is a schematic illustration of another system of the presentinvention having a plurality of chemical mechanical polishing stationsand anneal stations;

FIG. 9 is a schematic illustration of the anneal station of the presentinvention wherein the station has an anneal slot and an buffer slot tobe used as a buffer zone;

FIG. 10 is a schematic illustration of another embodiment of theintegrated chemical mechanical polishing processing station;

FIG. 11 is a schematic illustration of a chemicaltreatment/cleaning/rinsing-drying module of the of the integratedchemical mechanical polishing processing station of the presentinvention;

FIG. 12 is a schematic plan view of the chemicaltreatment/cleaning/rinsing-drying module of the present invention;

FIG. 13 is a schematic illustration of a chemicaltreatment/cleaning/rinsing-drying module of the of the present inventionwherein a wafer is cleaned by a cleaning mechanism of the module;

FIGS. 14A-14B are schematic illustrations of the roller brushes used inthe module;

FIG. 15 is a schematic illustration of the chemicaltreatment/cleaning/rinsing-drying module of the present inventionwherein the wafer is being picked up by a drying spindle after the waferis cleaned;

FIG. 16 is a schematic illustration of a chemicaltreatment/cleaning/rinsing-drying module of the of the present inventionwherein a wafer is spin dried by the drying spindle of the module; and

FIG. 17 is a schematic illustration of a system of the present inventionincluding a plurality of the chemical treatment/cleaning/rinsing-dryingmodules.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention will now be described in greater detail, whichwill serve to further the understanding of the preferred embodiments ofthe invention. As described elsewhere herein, various refinements andsubstitutions of the various embodiments are possible based on theprinciples and teachings herein.

The preferred embodiments of the present invention will be describedwith reference to FIGS. 1-17, wherein like components, parts, rollers,gears, tracks, motors, bars, etc. are designated by like referencenumbers throughout the various figures. Further, specific parameters andcomponents are provided herein, which are intended to be explanatoryrather than limiting.

The preferred embodiments will be described using the example of aworkpiece or wafer, but different applications such as packaging, flatpanel displays, and magnetic heads can be used with the presentinvention. The present invention describes a workpiece cleaning anddrying module. The cleaning and drying module of the present inventionis capable of processing workpieces with different diameters atdifferent times, but will typically process workpieces of the same sizefor a given processing run. The workpiece can be transferred from aplating or polishing processing module using a movable housing.

The present invention provides a system for semiconductor devicefabrication. The system comprises several process modules to performprocess steps such as Electrochemical Mechanical Processing (ECMPR),electrochemical deposition (ECD), chemical mechanical polishing (CMP)and electrochemical polishing (EC-polishing) integrated with otherprocess steps such as cleaning, edge bevel removal and drying. The termof Electrochemical Mechanical Processing (ECMPR) is used to include bothElectrochemical Mechanical Deposition (ECMD) processes as well asElectrochemical Mechanical Etching (ECME), which is also calledElectrochemical Mechanical Polishing (ECMP). It should be noted that ingeneral both ECMD and ECME processes are referred to as electrochemicalmechanical processing (ECMPR) since both involve electrochemicalprocesses and mechanical action.

Additionally, an integrated tool of the present invention is designed toutilize these process modules to perform multiple processing stepsrelated to electrochemical deposition, chemical mechanical polishing,and electrochemical polishing.

Following the ECD, ECMP, CMP or electrochemical polishing processes, theelectrolyte residues need to be rinsed off the wafer, and subsequentlywafer needs to be dried. Additionally, after such processes, it may benecessary to remove a portion of the metal that is deposited near theedge of the wafer surface. This process is often referred to as “beveledge clean” or “edge removal” step. In the present invention, certainexemplary process chambers, i.e., ECD, ECMPR, or electrochemicalpolishing chambers, and their respective cleaning chambers are stackedvertically, although there is also described herein an additional CMPchamber in which the cleaning chamber is horizontally disposed from thechemical mechanical polishing area. The edge removal step may be carriedout in the cleaning chamber, whether such cleaning chamber is verticallydisposed with respect to the process or not. In the context of thisapplication, the cleaning chamber is the chamber where cleaning (using afluid such as water or the like to remove residues therefrom) and dryingand possibly edge removal process steps are performed.

FIG. 1 illustrates an integrated tool 100 or system of the presentinvention which comprises a wafer processing section 102 and aload/unload section 104 or a cassette section connected to theprocessing section 102 through a buffer section 106. The processingsection 102 may comprise one or more electrochemical mechanical processstations or subsystems 108A-108C and one or more chemical mechanicalpolishing process stations or subsystems 108D, which are each configuredwith respect to a wafer handling section 109 within the wafer processingsection 102, as in the manner shown in FIG. 1. In this embodiment, theprocess stations 108A-108C may preferably be vertically stacked chambersthat have both an electrochemical mechanical deposition (ECMD) chamberand a cleaning chamber (i.e., ECMD/cleaning chamber).

As so configured, the integrated tool 100 of the present invention isable to process wafers with different diameters at different times, butwill typically process wafers of only the same size for a givenprocessing run. An exemplary vertical chamber design and operation forthe process chambers 108A-108C is disclosed in the U.S. Pat. No.6,352,623, entitled “Vertically Configured Chamber Used for MultipleProcesses,” commonly owned by the assignee of the present invention.

In a preferred sequence of operations, wafers 110 or workpieces to beplated are delivered to the cassette section 104 in a cassette 112 andthen each may be picked up and transferred to the buffer section 106 bya first robot 114. Each wafer 110 can then be transferred to one of theprocessing stations 108A-108C in the processing section 102 by a secondrobot 116. As mentioned above, the processing stations 108A-108D can beeither adapted to process 200 or 300 millimeter (mm) wafers, or othersize workpiece if desired. After the electro chemical mechanicaldeposition and cleaning processes are complete, each wafer istransferred into the chemical mechanical polishing processing station108D.

The chemical mechanical polishing processing station 108D, describedhereinafter, contains a wafer entry area 402 and a separate wafer exitarea 404 as shown in FIG. 4. As will be described hereinafter, thechemical mechanical polishing processing station 108D is particularlysuited for processing wafers that have had copper overburden depositedup to several thousand angstroms deposited that requires removal, withmost of the removal typically being obtained using the chemicalmechanical polishing processing station 108D. Wafers 110 are loaded intothe wafer entry area 402 (see FIG. 4) of the chemical mechanicalpolishing processing station 108D using the second robot 116, and thenremoved from the chemical mechanical polishing processing station 108Dat the wafer exit area 404 (see FIG. 4) using the first robot 114.

While the preferred sequence of operations is described above, it isnoted that the system 100 is capable of moving the wafers 110 from eachsubsystem to another subsystem, in an order different from that recitedabove. Accordingly, usage of certain processing subsystems withoutothers, as well as usage of processing subsystems in an order that isdifferent than that recited above are within the scope of the presentinvention.

FIG. 2 illustrates another embodiment of an integrated tool 200 orsystem of the present invention. In this embodiment, the processingstations 208A-208C are populated with various types of deposition tools,such as the electrochemical mechanical processing station 208A andelectrochemical processing station 208B and C. Each processing station208A-208C is preferably configured as a vertical chamber as describedabove and further described in the U.S. Pat. No. 6,352,623, entitled“Vertically Configured Chamber Used for Multiple Processes,” commonlyowned by the assignee of the present invention. This allows variationbetween the type of processing that is used, and thus more flexibilityin terms of the types of processing operations that can be performed.

The preferred sequence of operations is, nonetheless, the same as thatdiscussed previously with respect to FIG. 1, in which one of theprocessing stations 208A-208C is first used, and thereafter the chemicalmechanical polishing processing station 208D is used. Thus, processingsection 202, cassette 212 with cassette section 204, handling section209, buffer section 206, first robot 214, and second robot 216 operatein the same manner as processing section 102, cassette 112 with cassettesection 104, handling section 109, buffer section 106, first robot 114,and second robot 116 respectively described with reference to FIG. 1.

While the preferred sequence of operations is described above, it isnoted that the system 200 is capable of moving the wafers 210 from eachsubsystem to another subsystem, in an order different from that recitedabove. Accordingly, usage of certain processing subsystems withoutothers, as well as usage of processing subsystems in an order that isdifferent than that recited above are within the scope of the presentinvention.

It is also within the scope of the present invention that the abovesystems may also comprise an anneal chamber to anneal the wafers. Whenan anneal chamber is included, it is preferable to have the annealchamber located in proximity to the buffer area, and for the annealchamber processing subsystem to include both a “hot” section capable ofheating the wafer, and a “cool” section capable of cooling the waferafter annealing has been completed. Such an anneal chamber willtypically have the ability to operate upon a single wafer at a time, andis well known. Thus, further description is not believed necessary. Whatis advantageous with respect to the present invention is the manner inwhich the anneal chamber is integrated with the other processingsections, in order to maximize efficiency and throughput. In particular,as shown in FIG. 3, both of the robots 314 and 316 can place wafers intoor take wafers 310 out of the anneal chamber processing station 308E. Ifboth robots can perform such operation, as described below, then ifthere are no further operations after annealing, the anneal chamber canact as a substitute buffer area.

In a preferred operation mode, however, a further chemical mechanicalprocessing operation is performed after the anneal operation. In thisoperation mode, the integrated system 300 illustrated in FIG. 3 isadvantageous for the following reasons.

As illustrated in FIG. 3, integrated tool 300 or system of the presentinvention using an anneal chamber processing station 308E as describedabove. The anneal chamber processing station 308E includes a processingsection 302 and a load/unload section 304 connected to the waferprocessing section 302, as will be described in further detailhereinafter. Separate from, but disposed vertically with respect to theanneal chamber processing station 308E, is a buffer section 306 thatallows for movement of the wafer to and from the cassette 312 withincassette section 304, from and to the processing section 302 through thebuffer section 306. As will also be described hereinafter, this allowsfor the system 300 to be configurable, either with an anneal chamberprocessing station 308E or without the anneal chamber processing station308E.

The processing section 302 may comprise a first, second, third andfourth process stations 308A, 308B, 308C, and 308D in addition to theanneal chamber processing station 308E, which may be clustered aroundthe handling section 309, as in the manner shown in FIG. 3. While theprocess stations 308A-308D can each perform a different type of processtaken from the processes described above, in a preferred embodiment eachof the process stations 308A-308C are the same type of process stations,such as an ECMPR process station, and the station 308D is comprised of aCMP processing subsystem that has an entry area 402 and an exit area 404(see FIG. 4), as will be described further hereinafter.

In a preferred sequence of operations, wafers 310 or work pieces to beplated (with ECD and/or ECMD) are delivered to the cassette section 304in a cassette 312 and then each may be transferred to the buffer section306 by a first robot 314. Each wafer 310 may then be picked up andtransferred to one of the vertical chamber stations 308A-308C by asecond robot 316 so that plating and/or removal of conductive materialfrom the front surface of the wafer and an initial cleaning isperformed. Thereafter, the second robot 316 picks up the wafer 310 andtransfers it to the annealing chamber processing station 308E. Onceannealed and chilled within the annealing chamber processing station308E, the wafer 310 can then be picked up by the second robot 316 andtransported to the entry area 402 (see FIG. 4) of the CMP chamberprocessing station 308D. Once conductive material is removed from thefront face of the wafer using the CMP chamber processing station 308D,which processing station 308D will also perform cleaning as describedfurther herein, it is located in the wafer exit area 404 (see FIG. 4) sothat the first robot 314 can directly pick up and transfer the wafer 310to the cassette section 304.

While the preferred sequence of operations is described above, it isnoted that the system 300 is capable of moving the wafers 310 from eachsubsystem to another subsystem, in an order different from that recitedabove. In particular, it may be useful to perform the chemicalmechanical polishing operation prior to the annealing operation.Accordingly, usage of certain processing subsystems without others, aswell as usage of processing subsystems in an order that is differentthan that recited above are within the scope of the present invention.

FIG. 4 illustrates an overview of the chemical mechanical polishingprocessing station 400, which is then used for processing station 108Dillustrated in FIG. 1, 208D illustrated in FIG. 2, and 308D illustratedin FIG. 3. For purposes of FIGS. 4-7, the wafer being operated upon isdesignated wafer 410.

The chemical mechanical processing station 400 will be described indetail hereinafter. An initial overview of its operation is initiallyprovided. As is apparent from FIG. 4, the chemical mechanical polishingprocessing station 400 includes a movable input housing 414 receives awafer 410 from a second robot, such as robot 116 illustrated in FIG. 1,at a wafer input area 402. As shown in FIG. 4, the movable input housing414 can then move the wafer 410 disposed thereon between the wafer inputarea 402 and a chemical mechanical processing apparatus 420 thatchemically mechanically polishes the wafer 410. Another movable housing432 moves the wafer 410 between the chemical mechanical processingapparatus 420 and cleaning and drying areas that are covered by cover442, which cleaning and drying areas clean and dry the wafer,respectively. Within the cleaning and drying areas is also a waferoutput area 404 (depicted as a box in FIG. 4) from which location thewafer 410 can be removed from the chemical mechanical polishingprocessing station 400 by a first robot, such as robot 114 illustratedin FIG. 1.

In the description that follows, the chemical mechanical polishingprocessing station 400 will be described with reference to a singlewafer 410 that moves through the station 400. An advantage of thestation 400 that will be apparent from this description is that morethan one wafer 410 can be located within the station 400 at a time. Inparticular, at any given time, up to three wafers can be located withinthe system. With three wafers, one wafer is disposed on the movableinput housing 414, waiting to place its wafer on the chemical mechanicalprocessing apparatus 420, a second wafer is operated on by the chemicalmechanical processing apparatus 420, and a third wafer is operated uponwithin the cleaning and drying areas. This configuration thus improvesthroughput, as chemical mechanical polishing can take place on one waferand cleaning and drying can take place on another wafer at the sametime.

The chemical mechanical polishing processing station 400 will now bedescribed in more detail. The wafer entry area 402 mentioned previouslyincludes a plurality of at least three holding pins 418 mounted on amovable housing 414. The pins 418 are each configured so that the wafer410 will rest on a portion of each pin 418, with all of the pins 418thus supporting the wafer on the movable housing 414. With the wafer 410being supported by the pins 418, the movable housing 414 can be movedalong a track 438 between the wafer entry area 402 and the chemicalmechanical polishing processing apparatus 420. Movement of the movablehousing 414 preferably uses a cylinder (not shown) that is operatedunder electronic control 490 (shown in FIG. 5), which electronic controlis preferably computer based and operates using application softwarewritten to control the movement of the various components describedherein.

A robot, such as robot 116 in FIG. 1, will place the wafer 410 in thewafer entry area 402 so that the wafer holding pins 418 can hold it asdescribed above. Once so held, the movable housing 414 moves the wafer410 to the chemical mechanical polishing processing apparatus 420. Oncewithin the chemical mechanical polishing apparatus 420, the wafer 410 ispreferably centered using a centering apparatus 422. As illustrated inFIG. 4, the centering apparatus includes a rod 423 that is mechanicallymoved, such as by a piston, and laterally pushes the wafer so that it isproperly positioned using the top edge 418A of two of the pins 418 andthe end of the rod 423. This ensures that the wafer 410 is in properposition for the carrier head 426 to then pick up the wafer 410. Whenthe carrier head 426 picks up the wafer 410, the front surface of thewafer 410 is disposed in a down position and movement of the carrierhead 426 will allow the front surface to contact the pad or belt 424associated with the chemical mechanical polishing process. Chemicalmechanical polish processing, using either an abrasive pad or belt 424,or a slurry or both can take place in a conventional manner in thechemical mechanical polish processing apparatus 420, preferably with thecarrier head rotating and the chemical mechanical polishing apparatus420 having a polishing pad that either rotates or, most preferably,moves bi-linearly. With the most preferred bi-linear movement of thechemical mechanical polishing apparatus 420, the chemical mechanicalprocessing system uses a chemical mechanical polishing apparatus 420 asdescribed in U.S. Pat. No. 6,468,139, assigned to the same assignee asthe present invention.

Once chemical mechanical polishing in the chemical mechanical polishprocessing apparatus 420 is complete, another movable housing 432, towhich supports 434 that hold wafer holding spools 436 are attached, ismoved underneath the chemical mechanical polish processing apparatus420, with the movable housing 414 being moved to the wafer entry area402, awaiting receipt of another wafer. The wafer 410 is unloaded fromthe carrier head 426 onto the wafer holding spools 436. The holdingspools 436 are preferably round from a top view, made of a hard rigidmaterial that does not interact with the wafer and cleaning solutions,and have a lower lip 436A that is longer than an upper lip 436B. Thisconstruction allows for the release of the wafer 410 onto the lower lip436B when the spools 436 are in an open position. Once the wafer 410 hasbeen removed from the carrier head 426 onto the lower lip 436A of thespools 436, the spools 436 are then positioned into a closed positionusing a motor not shown that is controlled by the electronic control 490illustrated in FIG. 5. With the spools 436 in the closed position, thewafer 410 is tightly held at its edges between the lower lips 436A andthe upper lip 436B. With the wafer 410 in place, the movable housing 432transports the wafer 410 to cleaning and drying areas that are within anarea covered by cover 442.

Once the wafer 410 is within the cleaning area 440, a portion 442A ofcover 442 is lowered to cover the wafer 410 and the movable housing 432so that cleaning and drying processes can take place. As will bedescribed hereinafter, the cleaning process takes place while the waferis still attached to the movable housing 432, and, once cleaning occurs,a rotatable wafer transport device 460 will pick the wafer 410 off themovable housing 432 and rotate it for drying. Once the wafer 410 is dry,it will be held by the rotatable wafer transport device 460 in the exitarea 404 mentioned previously, the cover portion 442A will be raised,and then another robot, such as either robot 114 or robot 116 dependingupon the system configuration used, will pick up the wafer 410 from itsheld position on the rotatable wafer transport device 460 and transportthe wafer 410 to the next location.

FIG. 5 illustrates in further detail the components that are locatedwithin the cleaning and drying area 440. As illustrated, two cleaningrolls 452 and 454 are disposed on the front and back surfaces of thewafer 410, respectively, are moved over a portion the wafer 410 suchthat the entire radius of the wafer 410 is covered. The rolls 452 and454 are then rotationally driven, shown by a motor 456 and, controlledby electronic control 490, although other drive and control mechanismscould be used. With the rolls 452 and 454 spinning, the spools 436 arerotated using a motor, not shown, disposed within the movable housing432 and controlled by electronic control 490. Rotation of the spools436, each in the same rotational direction, cause rotation of the wafer410, so that each part of the front and back surfaces of the wafer 410contact one of the rolls 452 and 454 at some point in time during thecleaning process. During cleaning, as is known, a cleanser is typicallyapplied onto the wafer and the cleaning rolls remove residue left fromthe chemical mechanical polishing process, and then a DI water rinse isperformed using spray jets 458. As noted above, the rolls 452 and 454and the spray jets 458 will operate upon the wafer 410 while it is stillmaintained between the holding spools 436 on the movable housing 432.

Once the wafer has been cleaned, it must be dried. For drying, therotatable wafer transport device 460 is used to pick the wafer 410 offthe holding spools 436, raise the wafer to a rotation position, androtate the wafer to dry it. The components that make up the rotatablewafer transport device 460 include rotatable shaft 462 that is rotatedusing a motor 470 and drive components 472, and which is moved up anddown using up/down cylinder 474 connected through up/down drivecomponents 476, all of which are controlled through electronic control490. Attached to the rotatable shaft 462 is a wafer carrier 464 thatcontains clamps 466, the operation of which will be described furtherhereinafter in conjunction with the release mechanism 480 that is alsooperated through electronic control 490.

FIG. 6 illustrates a top view of the wafer 410 when it is positionedbetween the holding spools 436, and the orientation of clamps 466 withrespect to the holding spools 436 so that provision can be made toensure that the wafer 410 is not dropped. In the transfer of the wafer410, the holding spools 436 are retained in the closed position toensure their hold on the wafer 410 until the clamps 466 also have thathold, at which time the spools 436 are moved to the open position, andthe wafer 410 can move up, past the upper lips 436B of the spools whichare no longer holding the wafer 410. FIG. 7 further illustrates therelease mechanism 480, that is used to control the position of clamps466, so that at certain times the clamps are in a position that holdsthe wafer 410, and at other times are in an outward position so thatthey do not interfere with the wafer 410, as will now be described.

In the initial position after the wafer 410 has been cleaned asdescribed above, the wafer carrier 464 is disposed above the wafer 410so that the clamps 466 do not interfere with the cleaning operation. Therotatable wafer transport device 460 must then be moved into a positionto pick up the wafer 410. When this movement occurs, the clamps 466 mustbe disposed in an open position. This open position is ensured by usingthe release mechanism 480, which, through electronic control will causeactivation of the rod 483 associated with the release cylinder 482, andcause downward movement of release lever 484, and thus movement ofrelease bar 485. The downward movement of release bar 485 will cause theangled edge area 486 of the release bar 485 to move each horizontalrelease member 487, associated with each clamp 466, and thus cause eachclamp 466 to pivot outwardly around pivot point 465. This open positionof clamps 466 is maintained even during a power outage since the releasecylinder 482 is locked into with the rod 483 in the outward position,which requires another active signal from the electronic control 490 torelease the rod 483 that will thus allow the clamps 466 to close.

Once the clamps 466 are in the correct position for holding the wafer410, but still in an open position, the active signal is applied, andthe clamps automatically close, since the spring force from the springs488 will cause retraction of the horizontal release members 487, whichin turn will cause the upward movement of release bar 485.

With the clamps 466 in a closed position, the entire wafer carrier 464,along with the release mechanism 480, is moved to a spin position, wherethe wafer carrier 464, and thus the wafer 410, is rotated for drying.

Thereafter, the wafer carrier 464 is moved so that the wafer 410 is inthe exit position 404, and the wafer can be removed from the clamps 466onto another robot. It is noted that if a power outage occurs when theclamps 466 hold the wafer 410, that the bias from the springs 488 willstill retain the wafer 410 and it will not drop.

As shown in FIGS. 1-3, in these embodiments the wafer exit position 404is such that the first robot within the cassette section will pick upthe wafer. This reduces the number of transport tasks required of thesecond robot within the handling area of the processing section.

While the first robot within the cassette section can be used to pick upthe wafer from the wafer exit position, that is not necessary for allconfigurations. Rather, in certain configurations, the second robot canalso pick up the wafer from the wafer exit position.

One embodiment in which the second robot picks up the wafer from thewafer exit position is illustrated in FIG. 8, which embodiment shows aplurality of chemical mechanical polishing stations 808D, made asdescribed above, and which are used either with or without an annealprocessing station 808E. In this embodiment, the robot 816 in the waferhandling area 809 moves the wafers from the buffer 806 into either theanneal processing station 808E or one of the chemical mechanicalpolishing stations 808D. The first robot 814 disposed within thecassette section 804 will move the wafers from their cassette to thebuffer 806.

In each of the above embodiments, it is noted that it is desirable forthe first robot within the cassette section to pick up the wafer withthe front side up, and place the wafer with the front side down on thebuffer. Thereafter, the robot within the wafer handling area of theprocessing section, and each of the processing subsystems, will operateon the wafer with the front side down. While this is not required, itreduces complexity and minimizes movements of the wafer that could causedropping of the wafer.

FIG. 9 illustrates a view of the anneal chamber processing station 908Ein further detail. As illustrated, the anneal chamber processing station908E contains an open area 910 which allows the anneal chamberprocessing station 908E to be added to an existing system, with the openarea 910 corresponding to the position of the buffer 906. Thus, thebuffer 906 is disposed above or below (above as shown) the waferentry/exit area 912 of the anneal chamber processing station 908E.

In the various embodiments mentioned above, it has been noted that thepresent invention is capable of operating upon different sized wafers,which wafers are placed into a cassette section. The size of the waferin each of the different cassette is known through, for example, asoftware tag that is used by a system controller. Further, the robotarms that lift the wafers are configured so that they can detect thecenter of each wafer, regardless of size, and properly pick the waferup.

In addition, for each wafer, the system controller is also loaded withthe process sequence, or recipe, that is needed for that wafer, withvarious portions of the process sequence performed by differentprocessing stations. When sending a particular wafer to a particularprocessing station, that portion of the recipe can be sent in a commandby the system controller to a processing station module, and thatprocess can then take place, which then also allows tracking of thewafers that are being routed.

While in a production environment it is typical for each wafer to havethe same process sequence, and that is contemplated by the presentinvention as well, in certain research settings, have more control overthe processing of each wafer has been found beneficial. Thus, as eachwafer is transported to the appropriate processing station, which caninclude processing stations of the same type which operate upondifferent sized wafers, the system controller will track of the progressof the wafer through the system, so that coordination of the transportof the wafer from processing station to processing station can occur.

Each of the various subsystems that are referred to herein preferablycontain electronic control, such as the electronic control 490 describedwith respect to the chemical mechanical polishing apparatus 400, thatallow each of the various subsystems to operate in the integrated systemand independently. During operation with the integrated system, theelectronic control of each particular subsystem will work with thesystem controller to ensure that operations with other subsystems andthe wafer handling system are synchronized with the overall systemoperation. During operation of each subsystem independently, theelectronic control of the particular subsystem is capable of controllingthe operations performed by that particular subsystem. Accordingly,since subsystems can be used together and independently, the samesubsystems can be used in a greater variety of configurations, thusincreasing their flexibility.

FIGS. 10-16 illustrates a chemical treatment/cleaning/rinsing-dryingmodule in accordance with another embodiment of the present invention.The module of the present invention is able to perform chemicaltreatment, apply mechanical and megasonic cleaning means as well asrinse and dry processes in the same module. In general, the chemicaltreatment/cleaning/rinsing-drying module includes chemicaltreatment/cleaning/rinse devices and drying devices placed in anenclosure, and a movable housing. Chemical treatment/cleaning/rinsedevices may be roller brushes and various nozzles to spray DI water orthe chemical treatment solutions on the workpiece as well as megasonicnozzles. Drying devices may be a spinner to spin dry the workpiece. Theenclosure of the module has an opening to allow the movable housing inand out of the module.

The movable housing includes a support structure which includes holdersto hold a workpiece on the movable housing. The holders may be comprisedof support members and holding spools placed on top of the supportmembers. One of the holding spools can also be used as a driving spoolthat rotates the workpiece as the workpiece is held by the spools duringthe cleaning process. In this embodiment, the movable housing mayinclude a door, which closes and seals the opening of the module whenthe housing is inside the module. However, other mechanisms, which mayseal the opening of the module, may be used and is within the scope ofthis invention. Once the movable housing is inside the module, thedriving spool also engages a gear connected to a drive motor androtates. This, in turn, rotates the workpiece on the movable housingduring the cleaning done by the chemical treatment/cleaning/rinsedevices and drying device. Once the workpiece is cleaned, the dryingassembly picks up the workpiece and spin dries it. Although any othermeans of drying can also be used to dry the workpiece. After the spindrying process, the workpiece is transferred out of the module using arobotic arm.

FIG. 10 illustrates a simplified side view of a cluster tool 1100including an embodiment of a chemical treatment/cleaning/rinsing-dryingmodule 1104 in accordance with the present invention. In thisembodiment, the cluster tool 1100 may include a plating or polishingmodule 1102, the chemical treatment/cleaning/rinsing-drying module 1104,and a movable housing 1106. The tool 1100 may be used in any of thesystems described above in connection with FIGS. 1, 2, 3 and 8. Thechemical treatment/cleaning/rinsing-drying module 1104 will be referredto as module hereinafter. It is understood that the module 1104 may beused as an integral part of the tool 1100 or as an individualstand-alone chemical treatment/cleaning/rinsing-drying module. If theindividual version of the module is preferred the wafers may be fed andremoved manually or by a robot. As shown in FIG. 17, a plurality ofmodules may be placed in a system.

Although in the preferred embodiment the plating or polishing module1102 is a CMP module, it can be any process module used in the overallworkpiece manufacturing process such as ECMD, ECME or ECD. It isunderstood that the cluster tool shown in FIG. 10 is similar to the CMPprocessing station 400 shown in FIG. 4. Similar to the previousembodiment, a movable input housing (not shown) receives a wafer from arobot 116, such as the second robot shown in FIG. 1. The movable inputhousing (not shown) then moves the wafer to the CMP module 1102. Aworkpiece 1108 can be transferred from any module (i.e., the plating orpolishing module 1102) to the module 1104 using the movable housing1106.

The movable housing 1106 includes a center portion 1109 which isconnected to a base 1114. Support members, namely horizontal supportmembers 1110 and vertical support members 1111, are connected to thecenter portion 1109 by the horizontal support members 1110. As will bedescribed more fully below the workpiece 1108 is held over the verticalsupport members 1111. The movable housing 1106 includes the base 1114for moving the housing 1106 along tracks 1112. A door 1113 is connectedto the base 1114 and can be considered part of the housing 1106. Thehousing 1106 can be moved along the tracks 1112 using any known method.

In conjunction with the movable housing 1106, the module 1104 iscomprised of an enclosure 1105, a drying assembly 1200 and chemicaltreatment/cleaning/rinse assembly 1300 such as brushes, cleaningsolution nozzles, megasonic cleaner nozzles and their associatedcomponents.

The enclosure 1105 of the module 1104 includes an open end 1123 alongthe side wall of the enclosure. The open end 1123 is known as the entryand exit area for the movable housing 1106. When the housing 1106 is inthe module 1104, the entry and exit area 1123 of the housing 1106 issealed by the door 1113 when the movable housing 1106 is in the module1104.

The drying assembly 1200 is comprised of a rotatable wafer transportdevice 1202 or a spinner and a spinner moving assembly 1204. The spinner1202 of the module 1104 is comprised of a rotating shaft 1190 and aspinning wheel 1118 that is attached to the lower end of the shaft 1190.As will be described more fully below, the spinner 1202 is rotated bythe moving assembly 1204. Clamps 1136 for holding the workpiece 1108 areattached to the spinning wheel 1118 at its outer circumference. When thecleaning and spin drying processes are completed, the workpiece 1108 istransferred out of the module 1104 through the workpiece exit area 1140.The workpiece 1108 may be transferred out of the module 1104 using arobotic arm with a blade and vacuum. The workpiece 1108 can also betransferred out using any other known transfer apparatus and method.

FIG. 11 illustrates a side view of the module when the movable housing1106 is moved inside module 1104. The movable housing 1106 holds wafer1108 to be cleaned and spin dried while the entrance 1123 of the moduleis sealed by the door 1113 of the housing. In FIG. 11, the spinner is infully retracted position to allow cleaning of the workpiece. Aspreviously explained, in the previous embodiment, the housing retainsthe work piece such as a wafer upside down so that a front side 1108′ ofthe wafer 1108 faces down while a back side 1108″ of the wafer faces up.The front side of the wafer may be preprocessed using CMP. FIG. 12 showsmovable housing, in plan view, inside the module 1104. Referring toFIGS. 11 and 12, center portion 1109 of the movable housing is securedto the base 1114 in the center of the movable housing 1106. The housingis moved using the rails 1112 engaged both sides of the base 1114. Threeof the horizontal support members 1110 extend between the center portionand the vertical support members 1111 and radially uniformly disposedaround the center portion 1109. The angle between two horizontal supportmembers is preferably 120 degrees. In this embodiment, the housing hasthree horizontal and three vertical support members. The verticalsupport members 1111 are attached to the outer ends of the horizontalsupport members, and extend vertically and parallel to the vertical axis“A” of the center portion 1109. Referring to FIG. 11, the upper ends ofthe vertical supports 1111 further include spools or holding spools 1302that are used to secure the workpiece 1108 during the cleaning process.Holding spools are previously described above and in connection withFIGS. 4-5. The radial position of the vertical supports 1111 can bearranged to accommodate workpieces of different sizes (i.e., 200 mm, 300mm, etc.).

FIG. 11 also shows part of the spinner moving assembly 1204 and thespinner 1202. The spinner 1202 is attached to and is rotated by aspinner drive motor 1116 of the moving assembly 1204 that is located onthe ceiling 1183 of the enclosure 1105. The drive motor 1116 isinstalled on a platform 1315 that is further attached to an air cylinder1314 (see FIG. 15). The air cylinder 1314 shown in FIG. 15 moves thedrive motor 1116 and the spinner vertically up and down by the airpressure. The drive motor 1116 is attached to an upper end of the shaft1190 of the spinner.

Clamps 1136 of the spinning wheel hold the workpiece 1108 during thedrying process. Clamps 1136 are movably attached to the ends of arms1130 and are pneumatically controlled to pick up, hold and release theworkpiece before, during and after the spin-drying process. The spinningwheel includes three arms 1130. Airlines 1135 from an air supply (notshown) runs through the shaft and then distributed into the arms 1130 ofthe spinning wheel 1118. The clamps 1136 are moved into open and closedpositions by the pushers 1122′, 1122″ which are movably located at theends of the arms. The pushers 1122′ are spring loaded and bias and keepthe clamps in closed position. The pushers 1122″ are located at the endof the airlines 1135 in each arm 1130. In order to open the clamps,pressurized air from the air lines 1135 is used to move air activatedpushers 1122′ towards the clamps and thus cause each clamp to pivotoutwardly around pivot point P. When the air pressure is released, thepusher 1122′ causes clamps to pivot inwardly around the pivot point “P”and thereby closing them. The spinner and its components can becontrolled by an electronic control system similar to the one describedin the previous embodiment.

FIG. 13 shows a side view of the module 1104 with the chemicaltreatment/cleaning/rinse assembly 1300 including mechanical cleaners,such as a pair of rollers brushes 1132 and megasonic nozzle 1137 andspray nozzles 1141 a-1141 e. Nozzles are placed on the side walls orfloor of the enclosure 1105 of the module. In this embodiment, nozzle1141 a spray a solution depicted by S to the back side of the workpiece1108 while the nozzles 1141 b-1141 e are able to spray the solution S tothe front side of the workpiece while the workpiece is rotated on themovable housing 1106. In this embodiment, solution depicted by S may bea chemical solution to chemically treat the workpiece or DI water torinse the workpiece.

Referring to FIG. 12 and FIG. 13 brushes 1132 and megasonic nozzle 1137are shown in home position I and cleaning positions II and III. Theroller brushes clean the front and back sides 1108′, 1108″ of therotating wafer 1108 while rotating and performing a sweeping actionbetween the positions II and III. Various mechanical actions of thebrushes and the megasonic nozzle are controlled by a drive unit 1139. Aswill be described below, the workpiece is rotated on the movable housing1106 using a workpiece rotating mechanism. Megasonic nozzle is next tothe brush 1132 that works on the back side 1108″ of the workpiece.Megasonic nozzle 1137 generates megasonic waves during the cleaningprocess. In particular, megasonic waves dislodge the particulates thatare hard to remove using brushes. In this respect, the megasonic nozzlemay be used with the brushes at the same time or by itself before thebrush cleaning or again by itself after the brush cleaning.

FIG. 13 also illustrates a workpiece rotating mechanism 1123 inaccordance with the present invention. The workpiece 1108 can be rotatedusing one of the vertical supports, which will be referred to as drivesupport. The drive support includes a support gear. As previouslymentioned, one of the vertical supports 1111 is furnished with a drivemember that enables it to rotate. As this particular support rotates, italso rotates the spool 1302 on top of it. Rotation of the spool 1302 inturn rotates the wafer that is held by the spools. The support isrotated by a drive gear 1128 of the workpiece rotating mechanism 1123when support gear 1129 of the drive support engages the drive gear 1128of the workpiece rotating mechanism 1123. The drive gear 1128 isattached to a plunger 1126 that is movable placed in a sleeve 1127 whichallows the plunger 1126 to move back and forth and rotate in the sleeve.When plunger is rotated by a drive motor (not shown) attached on a sidewall, the drive gear 1128 rotates and also rotates the drive support.

As shown in FIGS. 14A and 14B, in one embodiment, roller brushes areused. They may be cylindrical and a cleaning solution may be deliveredthrough them. In this embodiment, the roller brushes 1132 may have aconical or tapered shape. In one manufacturing method, a brush section1400, which is cylindrical, is fitted onto a brush shaft 1410 that hasconical shape, thereby taking the shape of the shaft. This configurationeliminates the cleaning differential between the slow moving centralregion and the fast moving edge region of a workpiece or the waferduring brush cleaning. With conventional cylindrical roller brushes,cleaning of the slow moving central region of the wafer takes longertime. This cleaning differential may be avoided if a roller brush isable to exert more pressure on the central region than the edge region.This may be provided by making the brush conical so that a first end1420 of the brush that touches the central region of the wafer appliesmore pressure and speeds up the cleaning. A second end 1430 of the brushis narrower, thus exerts less pressure to the edge region of the wafer.Force applied onto the central region compensates the cleaningdifference that occurs due to the difference in velocities of edge andcentral regions of the wafer.

FIG. 15 shows the details of the moving assembly of the spinner 1202. InFIG. 15, the spinner is in fully extended position to pick up the waferfor drying process from the movable housing after the chemicaltreatment, cleaning and rinsing steps of the process. The drive motor1116 of the spinner is installed on the platform 1315 that is furtherattached to the air cylinder 1314. The air cylinder 1314 moves the drivemotor 1116 and the spinner vertically up and down. The drive motor 1116is attached to an upper end of the shaft 1190 of the spinner. Spring1117 is also attached to the platform 1315 for balance purposes.

FIG. 16 shows the module 1104 in side view in which the spinner 1202 haspicked up the wafer 1108 and fully retracted to spin dry the wafer 1180.During operation, once plating or polishing is completed, the movablehousing 1106 receives the workpiece on three holding spools installed onsupports 1111. As described earlier, the supports 1111 are attached tothe bars 1110 and the center portion 1109. As soon as a sensor (notshown) senses that the workpiece 1108 is positioned on the holdingspools, the workpiece 1108 is secured, and the movable housing 1106 ismoved into the module 1104 through the opening 1123. The door 1113 makescontact with the side wall of module 1104 and adjusts itself to providea proper seal. The movable housing 1106 then positions itself in thecenter of the module 1104.

When the movable housing 1106 is properly positioned, the drive supportgear engages with the gear on the plunger. The rotation of the drivesupport causes the workpiece 1108 to rotate. When the workpiece 1108 isrotating, cleaning rolls 1132 can then make contact with the top andbottom surfaces of the workpiece 1108 to begin the chemicaltreatment/cleaning/rinsing-drying process. Although it may be applied indifferent order, the process may include a chemical treatment firststep, a second step of brush and megasonic cleaning and a third step ofDI rinsing followed by spin drying. The chemical treatment step may beperformed by spraying acidic or basic solutions from the nozzles toclean the wafer. The nature of the solution depends on the material tobe cleaned. The chemical treatment solution may also contain apassivating agent (for corrosion prevention). A passivation step mayalso be performed using a passivation solution. For example, for postCMP copper cleaning of wafers, citric acid may be used to clean wafers.In this example, a passivating agent such as BTA may be used with thechemical treatment solution or rinsing water or by itself. Rollers andthe megasonic nozzle may be used during the chemical treatment or afterthe treatment as a separate cleaning step. After the chemical treatment,brush and megasonic cleaning, the wafer 1108 can be rinsed usingde-ionized water, as discussed earlier. The passivation agent may alsobe added to the rinsing water.

After the workpiece 1108 is rinsed, a drying process is required. Beforethe drying process, rotation mechanism is disengaged from the movablehousing to stop rotating the wafer. Clamps 1136 are used to pick up theworkpiece from the spools of the supports 1111. The spinner movesdownward and compressed air is delivered to the spinning wheel 1118. Thepushers 1122′ then push the clamps 1136 to an “open” position.Simultaneously, the center portion 1109 opens to release the workpiece1108. When air is shut off, the pushers 1122′ push the clamps 1136,thereby forcing them to contract on the workpiece 1108. Afterwards,spinning wheel 1118 with the workpiece 1108 is moved vertically upwardlyand the wheel 1118 and the workpiece 1108 are spun. After the workpiece1108 is dried, an outside robotic arm from location 1140 (FIG. 10)engages the workpiece 1108 so it can be transferred out of the module1104.

As shown in FIG. 17, a plurality of chemicaltreatment/cleaning/rinsing-drying modules, made as described above, mayform a system 1500. The system 1500 may comprise a cassette section1502, a buffer 1504, a wafer handling area 1505 and chemicaltreatment/cleaning/rinsing-drying modules 1506A-1506F. In thisembodiment, the robot 1508 in the wafer handling area moves the wafersfrom the buffer 1504 into one of the chemicaltreatment/cleaning/rinsing-drying modules. The first robot 1510 disposedwithin the cassette section 1502 will move the wafers from theircassette to the buffer 1504. In this embodiment location of the chemicaltreatment/cleaning/rinsing-drying modules may be configured side by sideas in the manner shown in FIG. 17, or any other configuration forexample the modules may be stacked on top of each other.

Although various preferred embodiments have been described in detailabove, those skilled in the art will readily appreciate that manymodifications of the exemplary embodiment are possible withoutmaterially departing from the novel teachings and advantages of thisinvention.

1. An integrated wafer processing system for processing a plurality of wafers comprising: at least one electrochemical mechanical polishing (ECMP) station to remove material from a front surface of each of the plurality of wafers; at least one chemical mechanical polishing station that contains separate wafer entry and wafer exit points; and a wafer-handling subsystem for transporting each of the plurality of wafers into and out of the at least one electrochemical mechanical polishing station and the at least one chemical mechanical polishing station.
 2. The system of claim 1, wherein each of the stations is disposed in a cluster arrangement adjacent the wafer-handling subsystem.
 3. The system of claim 1, wherein the wafer-handling subsystem includes at least one wafer-handling robot.
 4. The system of claim 1, wherein the wafer-handling subsystem comprises: a first wafer handling robot for removing each of the plurality of wafers from a cassette and placing the wafer in a buffer, and removing each of the plurality of wafers from the buffer and replacing the wafer in the cassette; and a second wafer handling robot for removing each of the plurality of wafers from the buffer and placing the wafer in one of the stations, and removing each of the plurality of wafers from the station and replacing the wafer in the buffer.
 5. An integrated wafer processing system for processing a plurality of wafers comprising: at least one electrochemical deposition station to deposit metal onto surfaces of the plurality of wafers in sequence; at least one electrochemical mechanical polishing (ECMP) station for removing metal from surfaces of the plurality of wafers; an annealing station; at least one chemical mechanical polishing station that contains separate wafer entry and wafer exit points; and a wafer-handling subsystem for transporting the plurality wafers into and out of the at least one electrochemical deposition station, the at least one electrochemical mechanical polishing station, the annealing station, and the at least one chemical mechanical polishing station.
 6. The system according to claim 5, wherein the annealing station includes an annealing area and a chilling area.
 7. The system of claim 5, wherein each of the stations is disposed in a cluster arrangement adjacent the wafer-handling subsystem. 